In order to generate electrical energy by means of wind energy on a relatively large scale, wind energy installations with ever higher outputs are produced. Often, a plurality of wind energy installations erected at one location are combined to form a wind farm. However, it is the case that it is precisely the locations with severe winds and which are suitable for erecting wind energy installations or wind farms with a high output are located in rural, sparsely populated areas. In these areas, the energy transmission system of the energy providers generally only has a low transmission power. It is not rare for this to result in corresponding restrictions applying to the operation as a result of the restricted transmission capacity of the energy transmission system. The operational limits of an energy transmission system are determined by power limits of the lines and components connected therebetween such as transformers. The operational limits of the energy transmission system necessitate a limitation which prevents it from being possible to utilize the full power of the wind energy installation or of the wind farm in favorable wind conditions. This results in economic disadvantages.